An ultra wide field fundus imaging system comprises a photosource, an optical splitter, a scanning assembly, a curved reflector, a probe pinhole and an imaging assembly. The scanning assembly includes a first scanning mirror scanning along a first direction and a second scanning mirror scanning along a second direction. The light emitted by the photosource passes through the optical splitter, then successively is reflected by the first scanning mirror, the curved reflector, the second scanning mirror and the curved reflector, and then enters in the fundus; the light entering the fundus is reflected by the retina and then successively is reflected by the curved reflector, the second scanning mirror, the curved reflector, the first scanning mirror and then returned to the optical splitter; the light is reflected by the optical splitter and passes through the probe pinhole, finally the light enters in the imaging assembly. Compared with the prior art, the ultra wide field fundus imaging system realizes fundus imaging by total reflection and can effectively avoid ghost images caused by lens module imaging to improve the imaging quality. Since the curvature of the curved reflector is gradually changed, so the light reflected by the curved reflector can enter in the fundus at a larger incident angle to achieve wide field imaging.